The diagonals of a square measure 14 cm. which is the length of a side of the square?

The diagonal of a square is given by:
 d = root (2) * L
 Where,
 L: length of the sides of the square.
 Substituting we have:
 14 = root (2) * L
 Clearing L we have:
 L = 14 / root (2) cm
 
 The length of a side of the square is:
 L = 14 / root (2) cm